My favorite is the Teva Mush flip flop. I have the Mush II but I'm sure the orginal Mush is just as good, if not better.
I started out loving CROCS. They were the best shoes for Disney or walking long distances (or so I thought). Even though they were comfortable, they did cause pain after a while. After a few days my feet were in pain and I felt like I was walking on fire. My legs hurt too.
I decided to try some Nike flip flops one trip and then I thought those were amazing. The memory foam was great. But again, it eventually started hurting my feet too. Less than the Crocs, but still. It didn't absorb impact as much as I had hoped and no arch support. I figured I would be in pain no matter what with all the walking I usually do at Disney.
Then on another trip I decided to try the Teva Mush flip flops. OMG. It's the most amazing flip flop ever. It absorbs impact, has arch support. Doesn't rub the bottom of your feet. I used to alternate between two kinds of shoes, but after trying the Tevas, the Crocs felt really uncomfortable. I can't even wear them anymore.
The Nikes were still fine, but not enough support. Now I think I'll just stick to the Teva flip flop. Maybe get another one and alternate.